Cigarette with paper wrapper treated for ember-charring action to prevent formation of high temperature smoke fractions in burning tobacco



Nov. 15, 1966 H. A. LEBERT 3,285,253

CIGARETTE WITH PAPER WRAPPER TREATED FOR EMBER-CHARRING ACTION TO PREVENT FORMATION OF HIGH TEMPERATURE SMOKE FRACTIONS IN BURNING TOBACCO Filed March 13, 1964 (CONVENTIONAL CIGARETTE) TIE: L

INVENTOR.

H ERBERT A LEBERT ATTORNEY United States Patent 3,285,253 CIGARETTE WITH PAPER WRAPPER TREATED FOR EMBER-CHARRING ACTION TO PREVENT FORMATION OF HIGH TEMPERATURE SMOKE FRACTIONS IN BURNING TOBACCO Herbert A. Lebert, 8 Corte Dorado, Millbrae, Calif. Filed Mar. 13, 1964, Ser. No. 351,616 2 Claims. (Cl. 13115) In my copending application on an Embossed Wrapper Cigarette for Preventing Formation of High Temperature Smoke Fractions in Burning Tobacco, Method and Apparatus for Embossing the Wrapper, Serial No. 300,5 80, filed in the United States Patent Office on August 7, 1963, now Patent No. 3,228,402, dated January 11, 1966, it was pointed out that the smoke fractions in cigarette smoke which are formed or distilled at the higher burning temperatures are harmful to the smoker and are not required to obtain satisfactory smoke, and those fractions coming off above 900 Fahrenheit are considered high temperature fractions.

Moreover, in the above-identified application, it was stated that the light aromatic, low temperature fractions can be driven oil? or out of the tobacco in the smoke producing zone by air that has been heated to the 400 to 900 Fahrenheit range, and it was therein proposed to keep the smoke producing air from being heated above that range. This was accomplished by providing a controlled air entrance space between the paper wrapper and the tobacco particles in the smoke producing zone directly in back of the glowing ember, the space being provided by embossed or raised spots on the inner surface of the paper wrapper to hold the rest of the paper away from the tobacco particles. In this copending application, the indrawn air passes over the ember, reaching the temperature to drive off or distill the low temperature smoke fractions, but the air is not heated to a high enough temperature to drive off or distill the high temperature smoke fractions, the latter being burned as the ember advances between drags or puffs on the cigarette.

In my United States Patent No. 2,667,170, dated January 26, 1954, entitled Crimped Wrapper for Cigarettes, triangular pleats are fashioned in the paper wrapper by a crimper to provide the required air entrance spaces.

Continuing research in the field of cigarette smoke control, i.e., keeping the high temperature formed smoke fractions from reaching the smoker, while allowing the low temperature smoke fractions to reach the smoker, has resulted in still another means for accomplishing the desired results, which forms the subject matter of the present application.

Briefly stated, it is now proposed to treat the paper wrapper so that the heat from the glowing ember will partially burn, i.e., char the paper wrapper and char and/ or shrink the layer of tobacco particles next to the paper for a substantially predetermined distance back from the point of contact of the paper wrapper with the glowing ember to provide air entrance passages, this charring taking place between puffs by the smoker.

This amount of the cigarette directly in back of the glowing ember represents that portion of the cigarette which will provide the smoke for the next drag or puff on the cigarette. This result is accomplished by adding an oxidizing agent to the paper wrapper to lower the burning point of the paper, whereby the latter will char from heat of the adjacent glowing ember, with the charred portion of the paper being impervious to the passage of air therethrough. Accordingly, all air (oxy- 3,285,253 Patented Nov. 15, 1966 gen) must still enter the cigarette under the paper wrapper to reach the tobacco in the smoke producing zone, with the incoming air passing over and around the glowing ember so as to preclude formation of the high temperature smoke fractions.

Other objects and advantages will appear as the specification continues. The novel features will be set forth in the annexed claims.

The invention relates to the treated paper wrapper per se and the cigarete construction.

Drawing For a better understanding of the invention, reference should be had to the accompanying drawing, forming part of this specification, in which:

FIGURE 1 is an elevational view, partly in section, disclosing a conventional cigarette and the manner in which the indrawn air enters the cigarette through the glowing ember;

FIGURE 2 is a view similar to FIGURE 1, disclosing my cigarette with paper wrapper treated for ember-charring action; and

FIGURE 3 is a fragmentary plan view on an enlarged scale of a modified form of the treated wrapper in which at least portions thereof are treated with the oxidizing agent.

While I have shown only the preferred forms of my invention, it should be understood that various changes, or modification, may be made within the scope of the annexed claims without departing from the spirit thereof.

Detail description Referring now to the conventional cigarette shown in FIGURE 1 on an enlarged scale, it will be noted that a paper wrapper A provides a sleeve surrounding a tobacco filler B. As the cigarette is smoked, the incoming air drawn in by the smoker must pass through the glowing ember C and into the smoke producing zone D directly in back of the glowing ember, the indrawn air being indicated by the arrows 10. The temperature of the glowing ember is about l600 Fahrenheit and, therefore, both the low temperature smoke fractions (range of about 400 to 900 Fahrenheit) and the high temperature smoke fractions (range of about 900 to 1600 Fahrenheit) will be driven olf or distilled. Thus the injurious high temperature smoke fractions will reach the smoker.

The cigarette shown in FIGURE 2 on an enlarged scale is the same as the cigarette disclosed in FIGURE 1, excepting for the fact that the paper wrapper A has been treated by the addition of an oxidizing agent. In either case, a grey or white ash 11 results as the glowing ember C advances toward the butt end 12 of the cigarette during smoking.

This treatment of the paper wrapper A will cause the Iheat from the glowing ember C to partially burn, i.e., char the paper wrapper for a substantially predetermined distance E -(for example, /8" but not limited thereto) back from its point of contact with the glowing ember. The distance E represents that portion of the cigarette which will provide the smoke for the next drag of puff on the cigarette since smoke is formed, i.e., distilled from the tobacco directly in back of and adjacent to the burning ember, i.e., in the smoke producing zone D.

Treatment of the paper wrapper A so that it will ohar for the distance E is accomplished by adding suitable oxidizing agent or material to the paper to lower the burning point or increase the burning action as compared to conventional cigarette paper which stays unchanged up to the burning ember for all practical purposes, as shown in FIGURE 1 of the drawing. The charred portion of the paper wrapper at the burning end of the cigarette is designated by the numeral 14.

While the treatment of the paper wrapper A will cause it to blacken and char, it is still impervious to the passage of air therethrough and all air (oxygen) must still enter the cigarette under the end of the paper to reach the tobacco in the smoke producing zone D. The charring action, however, has made a change in the cigarette for the distance E. Whereas, in a conventional cigarette the tobacco particles of the tobacco filler B closely contact the inner surface of the paper wrapper A at all points (see FIGURE 1), with the treated paper wrapper A the charring lac-tion creates a small space between the charred paper portion 14 and the tobacco particles which were in contact with the paper prior to the charring action. The charring action appears to cause the tobacco particles orginall-y in contact with the inner surface of the paper wrapper A to shrink away from the inner surface of the paper, as Well as causing the wrap-per itself to take up less space. This will create a small space designated at 15all with the result that air (oxygen) now has a free, low resistance path over and around the glowing ember C and into the smoke producing zone D-and at a much lower temperature than if it had been forced to pass through the glowing ember as is the case with the conventional cigarette.

The path of the indrawn air in the cigarette shown in FIGURE 2 is indicated by the arrows 16. When the smoker draws or puffs on the cigarette, with the paper wrapper A treated as described, the tobacco in the smoke producing zone D is distilled into low temperature aromatic smoke fractions (range of about 400 to 900 Fahrenheit) and the charred paper portion 14 is burned to white ash.

Between the puffs or drags on the cigarette by the smoker the advancing glowing ember C with its 1600 Fahrenheit temperature burns to completion the high temperature smoke fractions (range about 900 to 1600 Fahrenheit) still in the partially burned tobacco particles and, at the same time, provides enough heat to char a new distance E of the cigarette paper wrapper A In short, the stage is set for a repeat of the cycle described above.

Present cigarette paper manufacturing procedures call for a controlled burning ratea rate that keeps the paper intact and unchanged practically rightup to the burning ember C '(see FIGURE 1). Such manufacturing procedures can be altered to provide the burning rate that I proposed. I have been able to accomplish the desired action by wetting the paper with a weak solution of ammonium nitrate (NH NO and allowing the water to evaporate, thus leaving a deposit of the ammonium nitrate in the paper.

Ammonium nitrate decomposes at 410 Fahrenheita point below the charring temperature of the paperso when the cigarette is pulfed or drawn on and the distance E of charred paper is converted into white ash, the ammonium nitrate has already been driven off during the charring action between puffs. However, as the end products of ammonium nitrate are nitrogen (an inert gas) and water vapor, any small carry over of the originally very small amount used on the paper A is of small moment.

The basic idea of holding down the distillation temperature by flutes in the wrapper (Patent No. 2,667,170) or embossed points on the wrapper (copending application Serial No. 300,580), or by charring of the area where air passage is desired (present application), carries added value when viewed in light Olf the publication entitled Smoking and Health, Report of the Advisory Committee to the Sungeon General of the Public Health 4 ServiceU.S. Department of Health, Education, and Welfare (Public Health Service Publication No. 1103).

This report clearly points out that cigarette smoke is composed of two basic parts: (1) the particle phase and (2) the gas phase. Conventional filters attempt to take out some of the particle phase of the smoke as it moves on its way to the smoker. By contrast, the controlled temperature idea I propose, keeps the unwanted high temperature particle fractions from forming while the cigarette is being smoked and then burns these unwanted particle tfractions into the air between puffs by the smoker.

As to the gas phase of the cigarette smoke, the conventional filters cannot remove it without stopping all smoke fiowobviously impracticalso the harmful gas phase parts have to flow on to the smoker. However, since the harmful elements in both the particle phase and the gas phase are formed by pyrolysis action made possible by the very high distillation temperature which occur in the conventional cigarette, it is possible by holding down the distillation temperatures as herein described to prevent the formation of harmful particle phase elements and gas phase elements, while the smoker is puffing on the cigarette, and let these harmful elements burn into the atmosphere between puffs by the smoker as the ember C advances.

The cigarette paper wrapper shown in FIGURE 2 may be treated over its entire area with the oxidizing agent or material. In FIGURE 3, the modified cigarette paper wrapper A has been shown as being made with at least portions 17 having the oxidizing agent or material applied thereto. The portions 17 may take any suitable shape and arrangement, and I do not wish to be limited this respect. When the paper wrapper A is charred, the air passages will be formed under the charred portions or zones 17.

In either event, the air entrance passage will be small enough to preclude the smoke from being diluted with an excess of air.

I claim:

1. A cigarette paper wrapper treated with an oxidizing agent to lower the burning point of the paper, whereby the latter will char from heat of an adjacent glowing ember, with the charred portion of the paper being impervious to the passage of air therethrough, the oxidizing agent consisting of a solution of at least 10% strength ammonium nitrate that will decompose into nitrogen and water vapor at approximately 410 Fahrenheit, a point below the charring temperature of the paper.

2. A cigarette comprising:

(a) a paper wrapper providing a sleeve surrounding a tobacco filler;

(b) the paper wrapper being treated with an oxidizing agent to lower the burning point of the paper, whereby the latter will char for a substantially predetermined distance of approximately 6" back of a glowing ember at the burning end of the cigarette between puffs by the smoker, with the charred portion of the paper wrapper bein impervious to the passage of air therethrough and causing the tobacco particles originally in contact with the inner surface ff the paper to char and/or shrink away from the atter;

(c) the oxidizing agent being of a character for controlling the charring action to provide passages through which air may be drawn over and around the glowing ember and into the smoke producing zone directly in back of the glowing ember, during puffs by the smoker, so that the indrawn air will be lower in temperature range than if the air were drawn through the glowing ember, thus avoiding the distillation of high temperature smoke fractions of a range of about 900 to 1600 Fahrenheit;

(d) the charring action, under control of the oxidizing agent, providing passages that are small enough 6 so that the indrawn air will be heated to the proper References Cited by the Examiner range to drive 01f or distill the lower temperature smoke fractions of a range of about 400 to 900 UNITED STATES PATENTS Fahrenheit and preclude the smoke from being di- 1,983,530 12/1934 Bfand'enbefgef 131-15 lllted with excess air; 5 2, 8, 2 1/1'936 LOW 13115 (8) the said oxidizing agent consisting of a solution 2,171,986 9/ 1939 Poetschke 13115 of at least 10% strength ammonium nitrate that will discompose into nitrogen and Water vapor at ap- SAMUEL KOREN, Primary Examiner. proximately 410 Fahrenheit, a point below the charring temperature of the paper. 10 MELVIN REIN 

1. A CIGARETTE PAPER WRAPPER TREATED WITH AN OXIDIZING AGENT TO LOWER THE BURNING PINT OF THE PAPER, WHEREBY THE LATTER WILL CHAR FROM HEAT AND AN ADJACENT GLOWING EMBER, WITH THE CHARRED PORTION OF THE PAPER BEING IMPERVIOUS TO THE PASSAGE OF AIR THERETHROUGH, THE OXIDIZING AGENT CONSISTING OF A SOLUTION OF AT LEAST 10% STRENGTH AMMONIUM NITRATE THAT WILL DECOMPOSED INTO NITROGEN AND WATER VAPOR AT APPROXIMATELY 410* FAHRENHEIT, A POINT BELOW THE CHARRING TEMPERATURE OF THE PAPER. 